Problem: $ \left(\dfrac{7}{5}\right)^{3}$
$= \left(\dfrac{7}{5}\right)\cdot\left(\dfrac{7}{5}\right)\cdot \left(\dfrac{7}{5}\right)$ $= \dfrac{49}{25}\cdot\left(\dfrac{7}{5}\right)$ $= \dfrac{343}{125}$